Re: [Geopriv] Long review of draft-ietf-geopriv-loc-filters-07

["Hannes Tschofenig" <Hannes.Tschofenig at gmx.net>]

Here is another one: 


Draft Text:

-----

3.3. Element Value Changes
Changes in values, for example related to civic location information,
is provided by the base functionality offered with RFC 4661 utilizing
the <changed> element.
Figure 3 shows an example where a notification is sent when the civic
address tokens A1, A2, A3, or PC change (all 4 must change in order
to let the <trigger> element evaluate to TRUE).

------

Wow do I not
want that limitation. I want to be able to
tell when the device has crossed a city
boundary (into another city) while still
looking to see it the device has changed
states/territories yet.
I understand that PC changes might be
too often (but not always).
Is the alternative to have 4 separate
<changes> filters to get what I'm
describing here?
That seems clumbersome.

-----

This is how RFC 4661 works. Telling whether more than one PC changed
independently requires multiple <changes> filters. 

Ciao
Hannes


>-----Original Message-----
>From: Hannes Tschofenig [mailto:Hannes.Tschofenig at gmx.net] 
>Sent: 03 November, 2009 16:30
>To: 'Brian Rosen'; 'James Polk'; 'geopriv at ietf.org'
>Subject: RE: [Geopriv] Long review of draft-ietf-geopriv-loc-filters-07
>
>Hi James, 
>
>Thanks for your detailed review. I am in the process of 
>updating it and have comments here and there. 
>
>Here is one:
>
>Draft Text:
>
>--------
>
><?xml version="1.0" encoding="UTF-8"?>
><filter-set xmlns="urn:ietf:params:xml:ns:simple-filter">
>    <ns-bindings>
>        <ns-binding prefix="dyn" 
>            urn="urn:ietf:params:xml:schema:pidf:dynamic"/>        
>    </ns-bindings>
>    <filter id="123" uri="sip:presentity at example.com">
>        <trigger>
>            <changed by="3"> [<---James]
>              //dyn:speed
>            </changed>
>        </trigger>
>    </filter>
></filter-set>
>
>------
>
>[James] 
>
>I get the XML,
>but I don't see what the speed now is of the device/target?
>What if this device is moving at 200kmph, where would that be 
>placed in the XML?
>Of, is this left for the application at the subscriber to calculate?
>If the latter is true, something needs to be said about this 
>expectation.
>
>------
>
>The filter would not tell you what the current speed is. 
>
>The current document only supports 'by' and hence you cannot 
>say something like 'tell me when he goes faster than 100kmph'. 
>
>Ciao
>Hannes
>